SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2019-9813

Incorrect handling of __proto__ mutations may lead to type confusion in IonMonkey JIT code and can be leveraged for arbitrary memory read and write.

HIGH 8.8EPSS 7.39%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (7.39%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Incorrect handling of __proto__ mutations may lead to type confusion in IonMonkey JIT code and can be leveraged for arbitrary memory read and write. This vulnerability affects Firefox < 66.0.1, Firefox ESR < 60.6.1, and Thunderbird < 60.6.1.

CVSS 3.0
8.8 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
7.39% probability · 94th percentile
CISA KEV
Not listed
Weakness
CWE-843
Affected
mozilla/firefox · mozilla/thunderbird
Source
security@mozilla.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.